Comfy-Org/ComfyUI · error · ValueError

At least one image is required for editing.

Error message

At least one image is required for editing.

What it means

Dict-driven Grok image edit node requires at least one connected image: it collects non-None tensors from model['images'], sums their image counts, and n_images < 1 raises. All image sockets empty (or explicitly None) means the edit request would have no source image, which the xAI edits endpoint cannot process.

Source

Thrown at comfy_api_nodes/nodes_grok.py:584

    @classmethod
    async def execute(
        cls,
        prompt: str,
        model: dict,
        seed: int,
    ) -> IO.NodeOutput:
        validate_string(prompt, strip_whitespace=True, min_length=1)
        model_id = model["model"]
        resolution = model["resolution"]
        number_of_images = model["number_of_images"]
        images_dict = model.get("images") or {}
        aspect_ratio = model.get("aspect_ratio", "auto")

        image_tensors: list[Input.Image] = [t for t in images_dict.values() if t is not None]
        n_images = sum(get_number_of_images(t) for t in image_tensors)
        max_images = _GROK_IMAGE_EDIT_MAX_IMAGES.get(model_id, 3)
        if n_images < 1:
            raise ValueError("At least one image is required for editing.")
        if n_images > max_images:
            raise ValueError(
                f"The {model_id} model supports at most {max_images} input "
                f"image{'s' if max_images > 1 else ''}; {n_images} are connected."
            )
        if aspect_ratio != "auto" and model_id in _GROK_IMAGE_EDIT_ASPECT_RATIO_NEEDS_MULTIPLE and n_images == 1:
            raise ValueError(
                "Custom aspect ratio is only allowed when multiple images are connected to the image input."
            )

        flat_tensors: list[torch.Tensor] = []
        for tensor in image_tensors:
            if len(tensor.shape) == 4:
                flat_tensors.extend(tensor[i] for i in range(tensor.shape[0]))
            else:
                flat_tensors.append(tensor)

        response = await sync_op(

View on GitHub (pinned to 1c6d8d45b3)

Solutions

1. Connect at least one image to the node's image input(s).
2. Verify the upstream image node actually produced output (not None/empty).
3. Use a text-to-image Grok node if no source image is intended.

Example fix

# before
model['images'] = {}  # nothing connected -> raises
await grok_edit_execute(model, seed=1)

# after
model['images'] = {'image_1': load_image('src.png')}
await grok_edit_execute(model, seed=1)

n = sum(get_number_of_images(t) for t in (model.get("images") or {}).values() if t is not None)
assert n >= 1, "connect at least one image to the edit node"

When it happens

Trigger: Executing the model-dict grok image edit with model['images'] empty or every value None — nothing wired into any image socket.

Common situations: Workflow saved with image inputs that reference missing files; upstream node silently produced an empty dict; users attempting prompt-only generation through an edit node instead of a generation node.

Related errors

• The pro model supports only 1 input image.
• A maximum of 3 input images is supported.
• Custom aspect ratio is only allowed when multiple images are
• The {model_id} model supports at most {max_images} input ima
• The prompt references @Image{idx}, but only {total_images} r

AI-assisted analysis of Comfy-Org/ComfyUI@1c6d8d45b3 (2026-08-14). Data as JSON: /api/errors/2bc6069b9e194f1d. Report an issue: GitHub.